MDCT and MRI of the ampulla of Vater. Part I: technique optimization, normal anatomy, and epithelial neoplasms

Endoscopic papillectomy for synchronous adenoma of the major and minor duodenal papilla

OBJECTIVES

Synchronous adenomas of the major and minor duodenal papilla are seldom reported. The aim of this study was to describe the characteristics of synchronous major and minor papilla adenomas and to evaluate the safety and efficacy of endoscopic papillectomy (EP) for the management of the disease.

METHODS

Consecutive patients who underwent endoscopy for synchronous major and minor papilla adenomas from January 1, 2013 to August 31, 2023 were analyzed retrospectively. Patients' characteristics, clinical manifestations, laboratory, imaging and endoscopic findings were collected.

RESULTS

The nine patients with synchronous major and minor papilla adenomas had an average age of 50.78 ± 10.70 years. The diameter of major and minor papilla adenomas was 12.11 ± 3.41 mm and 6.11 ± 1.05 mm, respectively. Most major papilla adenomas had R0 horizontal margins (n = 8), while R0 vertical margins were achieved in all patients. While minor papilla adenomas were resected with both R0 horizontal and vertical margins in all patients. Post-EP bleeding was observed in one patient, which was classified as mild. Post-EP hyperamylasemia and pancreatitis was observed in two and four patients, respectively; the latter consisted of three with mild pancreatitis and one with severe pancreatitis. No perforation was observed. The mean follow-up duration was 9.22 ± 5.99 months. Histologically confirmed recurrence at the resection site was detected in one patient at 3 months after the procedure.

CONCLUSIONS

Synchronous major and minor papilla adenomas may not be as rare as previously speculated. EP may be an effective and safe alternative modality for their management.

Differentiation of malignant from benign ampullary strictures: A prediction nomogram based on MR imaging and clinical findings

PURPOSE

To construct a predictive nomogram based on contrast-enhanced magnetic resonance imaging (MRI) and clinical findings for differentiating malignant from benign ampullary strictures.

METHOD

In this retrospective study, 76 patients with ampullary strictures (51 benign and 25 malignant) who underwent contrast-enhanced MRI were enrolled. Imaging findings were evaluated independently by two abdominal radiologists who reached consensus. Clinical findings were also collected. Significant findings for malignant ampullary strictures were assessed by univariable and multivariable logistic regression analyses. Based on the results of multivariable analysis, a nomogram to differentiate malignant from benign ampullary strictures was developed and internally validated.

RESULTS

In multivariable analysis, presence of an ampullary mass (odds ratio [OR]: 8.42, p = 0.047), bulging ampulla (OR: 8.32, p = 0.033), diffusion restriction of the ampulla (OR: 42.76, p = 0.004) on MRI, and jaundice (OR: 12.41, p = 0.019) were significant predictors of malignant ampullary strictures. A predictive nomogram was constructed using these findings. Among them, diffusion restriction of the ampulla showed the highest OR and predictor score on the nomogram. The calibration plots for internal validation achieved strong agreement between the predicted probabilities and the actual rates of malignant ampullary strictures.

CONCLUSION

A combination of significant contrast-enhanced MRI and clinical findings of ampullary mass, bulging ampulla, diffusion restriction of the ampulla, and jaundice may be useful in the prediction of malignant ampullary stricture.

[Treatment of Ampullary Adenocarcinoma]

The ampulla of Vater is a small projection formed by the confluence of the main pancreatic duct and common bile duct in the second part of the duodenum. Primary ampullary adenocarcinoma is a rare malignancy, accounting for only 0.2% of gastrointestinal cancers and approximately 7% of all periampullary cancers. Jaundice from a biliary obstruction is the most common symptom of ampullary adenocarcinoma. In the early stages, radical pancreatoduodenectomy is the standard surgical approach. On the other hand, no randomized controlled trial has provided evidence to guide physicians on the choice of adjuvant/palliative chemotherapy because of the rarity of the disease and the paucity of related research. This paper reports the biology, histology, current therapeutic strategies, and potential future therapies of ampullary adenocarcinoma.

Research and analysis on computed tomography signs and clinical characteristics of chronic duodenal papilla mucositis and duodenal papillary carcinoma

Objective: To investigate the computed tomography (CT) findings of chronic duodenal papilla mucositis and duodenal papillary carcinoma, and provide more imaging information for early diagnosis of duodenal malignant diseases.Methods: CT findings and clinical data of 40 patients with chronic duodenal papilla mucositis and 46 patients with duodenal papillary carcinoma were retrospectively analyzed. Observation and measuring of direct duodenal papilla signs (including size, shape, density, enhancement uniformity, etc.), indirect duodenal papilla signs (including pancreaticobiliary dilatation) and clinical indicators (including tumor markers CA19-9, CA125, CEA, blood routine white blood cell count, bilirubin, age, gender, etc.) were carried out according to CT as well as statistical analysis.Results: There were significant differences in duodenal papilla regular morphology, age and CA19-9 (p < .05), and significant differences in duodenal papilla maximum transverse diameter, diameter of common bile duct, diameter of pancreatic duct, total bilirubin, direct bilirubin, and jaundice in duodenal papillary carcinoma group (p < 0.01). There were no significant differences in duodenal papilla enhancement uniformity, plain CT value, arterial CT value, portal CT value, enhancement uniformity, presence or not of calculus at the lower end, gender, CEA, CA125, white blood cell count, and abdominal pain with fever (all p > .05).Conclusion: CT is helpful for the diagnosis of duodenal papilla disease, but the CT findings of patients with duodenal papillary carcinoma tend to be similar to findings of chronic duodenal papilla mucositis, which is easy to lead to misdiagnosis, so comprehensive diagnosis should be made according to the direct and indirect CT signs as well as laboratory and clinical manifestations of duodenal papilla, so as to improve the diagnosis of duodenal papillary carcinoma, and reduce missed diagnosis and misdiagnosis.

Differentiating between benign and malignant ampullary strictures: a prediction model using a nomogram based on CT imaging and clinical findings

OBJECTIVES

To construct a predictive nomogram for differentiating malignant from benign ampullary strictures using contrast-enhanced computed tomography (CT) findings combined with clinical findings.

METHODS

In this retrospective study, 152 patients with ampullary stricture (98 benign and 54 malignant) who underwent contrast-enhanced CT were included. Various imaging findings of the ampulla, bile duct, main pancreatic duct, and periampullary area were evaluated and clinical findings including the presence of jaundice, carbohydrate antigen 19-9 level, and history of cholecystectomy were collected. Among them, statistically significant findings were identified using univariable and multivariable logistic regression analyses. A nomogram was constructed to differentiate benign and malignant ampullary strictures and was internally validated.

RESULTS

Multivariable analysis revealed that jaundice (odds ratio [OR]: 17.33, p < 0.001), presence of an ampullary mass (OR: 24.40, p < 0.001), non-similar enhancement of the ampulla to the duodenum (OR: 31.96, p = 0.003), and proportional dilatation of the bile duct (OR: 7.98, p = 0.001) were independent significant factors for predicting the malignant ampullary stricture, and were used to construct a nomogram. Among them, non-similar enhancement of the ampulla to the duodenum showed the highest OR and predictor point on the nomogram. The calibration plots showed excellent agreement between the predicted probabilities and the actual rates of malignant ampullary strictures, on internal validation.

CONCLUSIONS

Combination of clinical and imaging findings could aid in predicting malignant ampullary strictures using significant findings of jaundice, presence of ampullary mass, non-similar enhancement of the ampulla to the duodenum, and proportional dilatation of the bile duct.

KEY POINTS

• The presence of jaundice, ampullary mass, non-similar enhancement of the ampulla, and proportional bile duct dilatation were significant findings for predicting malignant ampullary strictures. • Non-similar enhancement of the ampulla to the duodenum was a significant feature with the highest odds ratio for differentiating benign and malignant ampullary strictures. • The nomogram constructed using contrast-enhanced computed tomography imaging and clinical findings could aid in predicting malignant ampullary strictures.

Ampullary Carcinoma: An Overview of a Rare Entity and Discussion of Current and Future Therapeutic Challenges

Ampullary carcinomas (ACs) represent a rare entity, accounting for approximately 0.2% of all gastrointestinal solid tumors and 20% of all periampullary cancers (PACs). Unfortunately, few data are available regarding the optimal therapeutic strategy for ACs due to their rarity, and physicians frequently encounter significant difficulties in the management of these malignancies. In this review, we will provide an overview of current evidence on AC, especially focusing on biological features, histological characteristics, and available data guiding present and future therapeutic strategies for these rare, and still barely known, tumors.

Metastatic rectal cancer in the ampulla of Vater: A unique case

Background

A metastatic lesion located in the ampulla of Vater is considered extremely rare, with only 32 cases reported globally.

Case

A 65‐year‐old patient was primarily diagnosed with a rectal adenocarcinoma. Twenty‐four months later as part of the oncological follow‐up, the patient was diagnosed with a single secondary tumor in the ampulla of Vater. After undergoing a pancreaticoduodenectomy (Whipple procedure), the patient experienced an uneventful recovery and received adjuvant chemotherapy. Sixteen months later the patient remained disease‐free.

Conclusion

To the best of our knowledge, the present case represents the first reported metastatic tumor in the ampulla of Vater, originating from a rectal adenocarcinoma. This case underlines the critical role of immunohistochemistry in arriving at a correct diagnosis in order to guide clinical decision‐making.

Recommendations for the Management of Incidental Pancreatic Findings in Adults by the Canadian Association of Radiologists Incidental Findings Working Group

The Canadian Association of Radiologists Incidental Findings Working Group consists of both academic subspecialty and general radiologists and is tasked with adapting and expanding upon the American College of Radiology incidental findings white papers to more closely apply to Canadian practice patterns, particularly more comprehensively dealing with the role of ultrasound and pursuing more cost-effective approaches to the workup of incidental findings without compromising patient care. Presented here are the 2021 Canadian guidelines for the management of pancreatic incidental findings. Topics covered include anatomic variants, fatty atrophy, pancreatic calcifications, ductal ectasia, and management of incidental pancreatic cysts.

Imaging of Ampullary and Periampullary Conditions

The ampulla of Vater is formed by the union of the pancreatic duct and the common bile duct and is also known as hepatopancreatic ampulla or hepatopancreatic duct. The ampulla is surrounded by a muscular valve known as the sphincter of Oddi, which controls the flow of bile and pancreatic juices into the duodenum in response to food. The ampulla is also an important embryological landmark as it marks the anatomical transition from foregut to the midgut. Because of this, it is a watershed zone where the blood supply changes from the celiac axis to the superior mesenteric artery. Radiologic evaluation of the ampulla and the periampullary region is challenging because it requires an understanding of the embryology, the normal appearance, and different anatomic variants. Also, a wide variety of pathologies can occur in this region. The purpose of this review is to present the normal anatomy of the ampulla and the periampullary region on different imaging modalities and to summarize the imaging features of the common variants, and benign and malignant ampullary and periampullary conditions. Understanding of the normal anatomical appearance and variants along with the knowledge of common pathologic conditions affecting the ampulla and periampullary conditions can help radiologists in making accurate diagnosis resulting in optimum patient care.

Duodenal tumors on cross-sectional imaging with emphasis on multidetector computed tomography: a pictorial review

Duodenal tumours are uncommon, but they can cause significant morbidity and mortality. As stomach and colon are a more common site of gastrointestinal malignancies, radiologists sometimes neglect the duodenum. Multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) can accurately locate and characterize mass-forming duodenal lesions, making them invaluable for the differential diagnosis and determining management strategies such as biopsy or surgery. Although conventional endoscopy continues to play an important role in the diagnosis of duodenal tumors, MDCT and MRI are very useful for evaluating the duodenal wall, extraduodenal space, and surrounding viscera, as well as the intraluminal content seen on endoscopy. This pictorial review aims to illustrate the most common benign and malignant mass-forming duodenal lesions and to focus on the imaging features that are most helpful in reaching the correct diagnosis.

Radiologic Evaluation and Structured Reporting Form for Extrahepatic Bile Duct Cancer: 2019 Consensus Recommendations from the Korean Society of Abdominal Radiology

Radiologic imaging is important for evaluating extrahepatic bile duct (EHD) cancers; it is used for staging tumors and evaluating the suitability of surgical resection, as surgery may be contraindicated in some cases regardless of tumor stage. However, the published general recommendations for EHD cancer and recommendations guided by the perspectives of radiologists are limited. The Korean Society of Abdominal Radiology (KSAR) study group for EHD cancer developed key questions and corresponding recommendations for the radiologic evaluation of EHD cancer and organized them into 4 sections: nomenclature and definition, imaging technique, cancer evaluation, and tumor response. A structured reporting form was also developed to allow the progressive accumulation of standardized data, which will facilitate multicenter studies and contribute more evidence for the development of recommendations.

Homogenously isoattenuating insulinoma on biphasic contrast-enhanced computed tomography: Little benefits of diffusion-weighted imaging for lesion detection

The aim of the present study was to evaluate the diagnostic benefit of diffusion-weighted imaging (DWI) in the detection of homogenous isoattenuating insulinoma on biphasic contrast-enhanced computed tomography (CT) preoperatively and to determine which magnetic resonance (MR) sequences exhibited the best diagnostic performance. A total of 44 consecutive patients who underwent biphasic contrast-enhanced CT and conventional MR imaging (MRI), including DWI on a 3T scanner, were identified retrospectively. Apparent diffusion coefficient (ADC) values of insulinomas and the surrounding pancreatic parenchyma were compared using a Wilcoxon signed-rank test. Receiver operating characteristic analysis was used to compare the diagnostic accuracy of four randomized image sets [T2-weighted image (WI), axial T1WI, DWI and T2WI + DWI] for each reader. Axial T1-weighted MRI exhibited the highest relative sensitivity for each reader; DWI alone exhibited the lowest relative sensitivity and the lower inter-reader agreement. There was no significant difference in lesion detection between T2WI and T2WI + DWI image sets for each reader. The ADC values of the insulinoma were significantly lower compared with those of the surrounding parenchyma. In conclusion, DWI does not benefit the detection of homogenous isoattenuating insulinoma. Axial T1WI is the optimal pulse sequence. Quantitative assessment of the tumor ADC values may be a useful tool to characterize identified pancreatic neoplasms.

Value of 64-row helical CT in diagnosis of duodenal papillary diseases

AIM

To assess the value of 64-row helical CT in the diagnosis of duodenal papillary lesions.

METHODS

Fifty-eight patients with duodenal papillary lesions treated at our hospital from February 2014 to August 2017 and 30 subjects without duodenal papillary lesions were included in this study. All subjects underwent 64-row helical CT examination to observe the maximum transverse diameter, shape of papillary lesion, pattern of enhancement, and the degree of enhancement.

RESULTS

Of 58 cases of duodenal papillary lesions, 38 were diagnosed as duodenal papillary carcinoma, 10 as duodenal papillary adenoma, 4 as duodenal papillary polyps, and 6 as duodenal papillitis. Duodenal papillary carcinoma had the largest maximum transverse diameter (20.35 mm ± 6.8 mm), followed by duodenal papillary adenoma (16.32 mm ± 6.04 mm), duodenal papillary polyps (12.86 mm ± 2.56 mm), duodenal papillonitis (9.34 mm ± 3.18 mm), and normal duodenal papilla (5.26 mm ± 1.02 mm). The maximum transverse diameter of duodenal papillary lesions was significantly larger than that of normal duodenal papilla, while there was no significant difference between duodenal papillary carcinoma and duodenal papillary adenoma (P = 0.58, P > 0.05). In 38 cases of duodenal papillary carcinoma, 22 (57.89%) were round in shape, and 16 (42.11%) had an irregular shape. In 10 cases of duodenal papillary adenoma, 8 (80.0%) were round and 2 (20%) were irregular. The average CT values of duodenal papillary adenocarcinoma, adenoma, inflammation, and polyps were comparable. Thirty-eight (78.95%) cases of duodenal papillary adenocarcinoma were uniformly enhanced. In 10 cases of duodenal papilloma, 6 (60.0%) were uniformly enhanced.

CONCLUSION

The diagnosis of a duodenal papillary lesion can be improved by comprehensive analysis of its maximum size, shape, and the degree of enhancement.

Surgical Ampullectomy with Complete Resection of the Common Bile Duct: a New Procedure for Radical Resection of Non-invasive Ampulloma with Biliary Extension

Extension of ampulloma into the lower common bile duct (CBD) is observed in up to 30% of cases. This biliary extension can prevent complete tumor resection thus is considered as a contraindication for endoscopic and even surgical ampullectomy. For ampullomas associated with a prolonged biliary extension, a pancreaticoduodenectomy is associated with a high morbidity and can be considered as an overtreatment for a benign neoplasm. The present study describes a new surgical approach including ampullectomy with complete resection of the intrapancreatic CBD and restoration of both biliary and pancreatic flow by two separate anastomoses. This procedure was performed in seven patients for a non-invasive ampulloma with a 25- to 70-mm CBD involvement. No patients died and three developed postoperative complications. Resection was R0 in all patients but one. With a 24-month median follow-up (range = 3-84), no patients developed pancreatic insufficiency or tumor recurrence.

Pathologic Subtypes of Ampullary Adenocarcinoma: Value of Ampullary MDCT for Noninvasive Preoperative Differentiation

OBJECTIVE

The purpose of this study was to evaluate the utility of ampullary MDCT in the noninvasive, preoperative differentiation of pancreatobiliary and intestinal subtypes of ampullary adenocarcinoma.

MATERIALS AND METHODS

This retrospective study included 32 patients (20 men, 12 women; age range, 41-81 years) with resected ampullary adenocarcinoma who underwent preoperative contrast-enhanced ampullary MDCT. Two radiologists, blinded to pathologic diagnosis of adenocarcinoma subtype, evaluated the presence of seven MDCT features independently. MDCT findings and ampullary adenocarcinoma subtypes were correlated using chi-square and Fisher exact tests. Interobserver agreement was evaluated using the Cohen kappa statistic.

RESULTS

When evaluated with ampullary MDCT, the intestinal and pancreatobiliary subtypes were significantly different in terms of lesion morphology (p < 0.0001), papillary shape (p < 0.0001), common bile duct (CBD) infiltration and dilatation (p = 0.003 and p = 0.0004, respectively), duodenopancreatic groove infiltration (p = 0.0009), and pancreaticoduodenal artery involvement (p = 0.004). Pancreatobiliary subtype tumors were more often infiltrative in morphology (18/18) and showed retracted papilla (14/18), CBD (18/18) and main pancreatic duct (MPD) infiltration (12/18), dilated CBD (18/18) and MPD (13/18), fixed duodenopancreatic groove appearance (15/18), and pancreaticoduodenal artery involvement (12/18). Intestinal subtype carcinomas were more frequently nodular (14/14) and had a bulging papilla (13/14), a free duodenopancreatic groove appearance (11/14), and no pancreaticoduodenal artery involvement (2/14). When all features were taken into account, MDCT showed sensitivity of 85.7% and specificity of 83.3% in differentiating intestinal and pancreatobiliary subtype tumors. Accuracy, positive predictive value, and negative predictive value of MDCT were 84.4%, 80%, and 88.2%, respectively. Interobserver agreement was almost perfect for the presence of each imaging feature (κ > 0.8).

CONCLUSION

Ampullary MDCT can be useful to differentiate pancreatobiliary and intestinal subtypes of ampullary adenocarcinoma preoperatively, provided the duodenum is optimally distended at imaging.